This application claims priority to Great Britain Patent Application No. 0105905.4 filed Mar. 9, 2001, which application is herein expressly incorporated by reference.
The present invention relates to a valve device and a method of connecting a container filled with a flowable material, such as fertilizer, pesticide or the like, to a receptacle, for instance of an applicator device for dispensing the material.
It is known to provide dispensing or applicator devices for distributing fertilizer or pesticide in a field. Containers of the fertilizer or pesticide may be provide for attachment to the dispensing or applicator device, such that, when a container is empty, it may be removed and replaced with a full one.
It is preferable that users of the dispensing device do not come into contact with the material in the containers.
EP-A-0389919 discloses a valve system for controlling the flow of a flowable agricultural treatment agent from a container for the material to a receiving chamber or hopper. The container has a material dispensing valve and the chamber or hopper has a material receiving valve. The dispensing valve and the receiving valve are adapted to be coupled and uncoupled so that, on being coupled, both valves are opened to allow material to flow from the container to the hopper and, on being uncoupled, both valves are biassed to a closed position.
Although this system prevents the user from coming into contact with the material in the container, it is relatively complex and expensive.
EP-A-0685155 discloses a valve device comprising a cylindrical housing in which a cylindrical valve member is axially displaceable. The housing includes a valve seat around the inner end of a flow passage and the cylindrical valve member has a valve disk which selectively seals with the valve seat. In particular, by virtue of a cam groove, relative rotation of the two cylinders causes them to move towards or away from one another and thereby close or open the valve.
This valve device still has a number of disadvantages. In particular, it requires the two halves of the valve device to move axially which, in turn, requires the container to move axially with respect to the receptacle to which it is attached. Also, closing the valve may be difficult when the valve plate has to move against a weight of flowable material. Furthermore, the available through passage for the flowable material is limited to the peripheral space around the valve disk when it is moved away from the valve seat.
It is an object of the present invention to provide an alternative valve device which is relatively simple and which achieves automatic opening and closing when being attached to or detached from a receptacle.
According to the present invention, there is provided a valve device for connecting a container filled with a flowable material to a receptacle and for dispensing the flowable material from the container into the receptacle, the valve device including an outer sleeve having a first end to be secured to the orifice of a container, a second end for releasable attachment to a receptacle and walls defining a generally cylindrical support passage extending from said first end to said second end, an inner sleeve within the support passage having walls defining a generally outer surface adjacent the walls of the outer sleeve so as to rotatably support the inner sleeve and defining an internal through passage, a butterfly valve member within the through passage having diametrically opposed first and second pivot stubs extending at least into the walls of the inner sleeve and rotatably supported by the walls of one of the inner and the outer sleeve wherein the walls of the other of the inner and outer sleeve are shaped so as to interact with at least the first pivot stub such that relative rotation of the inner and outer sleeve causes the butterfly valve member to rotate between a closed state in which the butterfly valve member closes the through passage by substantially filling an internal cross-section of the through passage and an open state in which the through passage is open.
Thus, the valve member may be provided in or adjacent the orifice of a container and normally have the butterfly valve member in a closed state. By rotating the inner and outer sleeves relative to one another, for instance as a part of engaging the valve device with a receptacle for the flowable material, the first pivot stub and, hence, the butterfly valve member are rotated to an open position to allow flow through the valve device.
In use, once a container has been connected to a receptacle using the valve device, the flowable material can all be dispensed into the receptacle and then the valve device and container detached. However, in a preferred application, the container and valve device are left connected until more material is required. In this way, the receptacle does not have to receive all of the flowable material at once and is supplied from the container according to its needs.
No axial movement is required to open and close the valve and, with the butterfly valve fully open, the only restriction to flow is the thickness of the butterfly valve itself. Furthermore, by virtue of the property of a butterfly valve that one side moves in a direction opposite to the other side, moving the valve against the flowable material is made easier, since material will merely flow from one side of the passage to the other.
The flowable material is preferably of solid form, for instance of granular form, but might also be liquid if the valve is designed to seal appropriately.
The butterfly valve itself preferably comprises a plate-like member having a shape corresponding to the internal cross-sectional area of the inner sleeve. This is preferably circular, but could be square or any other cross-sectional shape. The plate-like member may have a shape corresponding to an internal cross-sectional area which is angled, i.e. not perpendicular, to the axis of the inner sleeve so that it cannot rotate within the inner sleeve beyond that position. The butterfly valve then includes a rotational axis through approximately its middle and in its own plane.
The first and second pivot stubs can be rotatably supported in the outer sleeve and pass through apertures in the inner sleeve shaped so as to rotate the butterfly valve. In this case, the pivot stubs need not extend right through the outer sleeve, but may be supported in indented portions.
On the other hand, the first and second pivot stubs may be rotatably supported by the inner sleeve. In which case, only the first pivot stub need pass through the inner sleeve so as to interact with the outer sleeve and the second pivot stub could be supported merely by an indented portion in the walls of the inner sleeve.
The interacting sleeve may have walls shaped in any appropriate way to rotate the first pivot stub. For instance, an elongate aperture having teeth along one surface may interact with teeth provided around the outer periphery of the first pivot stub. Alternatively, an end face of the first pivot stub may be provided with a radially extending slot interacting with a pin or provided with a cranked pin interacting with a slot.
Preferably, the walls of the other of the inner and outer sleeves include a profiled opening and the first pivot stub extends into the profiled opening and includes a cam member such that relative rotation of the inner and outer sleeves causes interaction of the cam member and the profiled opening to rotate the butterfly valve member between the closed and opened states.
Of course, the profiled opening may be provided in either of the inner or outer sleeves, provided that the first and second pivot stubs are rotatably supported by the other of the inner and outer sleeves.
Preferably, the cam member extends radially of the first pivot stub. In this way, lateral movement applied to the cam member will cause rotational movement of the first pivot stub and the butterfly valve member.
Preferably, the profiled opening is generally trapezoid in shape having a long portion extending circumferentially with respect to the generally cylindrical support passage along which the first pivot stub moves with relative rotation of the inner and outer sleeves and a short portion extending circumferentially with respect to the generally cylindrical support passage into which the cam member extends, the cam member being deflected by the walls of the other of the inner and outer sleeves joining the long and short portions so as to rotate the butterfly valve member.
Thus, an elongate trapezoidal opening is provided in a circumferential direction of the inner and outer sleeves. While the rotational part of the first pivot stub is free to move along the entire length of the long portion, the radially extending cam member is restricted to move only the length of the short portion. Hence, as the rotational part of the first pivot stub moves from one end of the long portion to the other, at some point, the cam member will come into contact with an end wall of the profiled opening, be constrained from movement and, hence, rotate the first pivot stub.
In a preferred embodiment to be described, the short portion is positioned symmetrically with respect to the centre of the long portion. However, by angling the cam member differently with respect to the butterfly valve member, it is also possible for the short portion to be offset to one side with respect to the long portion.
Preferably, the first and second opposed pivot stubs are rotatably mounted in the walls of the inner sleeve and the walls of the inner sleeve include at least a first through hole for rotatably supporting the first pivot stub, the walls of the outer sleeve including the profiled opening and the first pivot stub extending through said first through hole into the profiled opening. In this way, the inner sleeve, through which the flowable material passes, has a relatively uninterrupted surface, only requiring a through hole for the first pivot stub and an indented support portion for the second pivot stub. Furthermore, as will be described below, it becomes possible to operate the butterfly valve automatically as part of a bayonet fitting.
Preferably at least one of the first and second pivot stubs extend beyond the periphery of the outer sleeve so as to form a bayonet pin for interacting with a bayonet groove of a receptacle. Thus, when the valve device is inserted into a female bayonet fitting and rotated, the or both pivot stubs which form bayonet pins are constrained from movement while the outer sleeve is rotated. In this way, the inner sleeve and the first pivot stub are rotated relative to the outer sleeve such that the first pivot stub interacts with the outer sleeve so as to open or close the butterfly valve member. Of course, the pivot stubs could be inserted into grooves in the female bayonet fitting of the receptacle other than the L-shaped grooves for securing the valve device in place, provided those grooves restrain movement of the pivot stubs so as to cause relative rotation between the pivot stubs and the inner sleeve with the outer sleeve.
As an alternative, the walls of the outer sleeve preferably include a first circumferentially extending aperture and the inner sleeve includes a first bayonet pin extending through the aperture for interacting with a bayonet groove of a receptacle, the circumferential extent of the aperture being sufficient to allow relative rotation of the inner and outer sleeves to cause the butterfly valve member to rotate between the closed and open states. Thus, similarly to described above, when inserted in a female bayonet fitting, the bayonet pin will be restrained from movement, such that the outer sleeve will be rotated relative to the inner sleeve. Similarly, the bayonet pin may engage grooves other than the L-shaped grooves of the bayonet fitting.
Preferably, the walls of the outer sleeve include a second circumferentially extending aperture and the inner sleeve includes a second bayonet pin extending through the second aperture for interacting with a bayonet groove of a receptacle, the circumferential extent of the second aperture being sufficient to allow relative rotation of the inner and outer sleeves to cause the butterfly valve member to rotate between the closed and open states. In this way, for a bayonet fitting including two bayonet pins, both bayonet pins may be provided on the inner sleeve. Preferably, the first and second apertures are diametrically opposed and the first and second bayonet pins are diametrically opposed. This is the preferred arrangement for a two-pin bayonet fitting.
Preferably, the valve device further includes an actuation shaft wherein the inner sleeve includes a pair of diametrically opposed support openings for supporting the actuation shaft there between, the actuation shaft extending outwardly of the support openings so as to form the first and second bayonet pins.
The actuation shaft may be positioned parallel with and actually offset from the axis of the butterfly valve member and, with an appropriate spacing there between, can be used as a stop for the butterfly valve member. Hence, preferably, the first aperture is axially aligned with the profile opening and the centre of the first bayonet pin is axially aligned with the centre of the first pivot stub.
The walls of the other of the inner and outer sleeves and the first pivot stubs are shaped so as to interact with lost motion such that the butterfly valve member is rotated between the closed and open state only after some intermediate relative rotation of the inner and outer sleeves. With the bayonet arrangement discussed above, this ensures that the pins of the bayonet are fully engaged before the butterfly valve member is opened. Thus, the inner and outer sleeves may be relatively rotatable only between two predetermined relative orientations and the butterfly valve member rotates between the closed and open states only as the inner and outer sleeves approach and are in the vicinity of the predetermined relative orientations.
Of course, a bayonet arrangement for the valve device will itself introduce some lost motion, since the outer sleeve will not rotate relative to the inner sleeve until the bayonet pins reach the end of the bayonet channels, thereby ensuring that the valve device is secured to the receptacle. The walls of the outer sleeves may further define a generally cylindrical outer surface for fitment to a receptacle. Thus, the bayonet fitting may be formed from the outer surface of the outer sleeve.
However, the valve device may further comprise an outer housing within which the outer sleeve is supported. The outer housing may cover only part of the outer housing, for instance to conceal parts, such as the profiled opening, interacting with the first pivot stub.
However, the housing may include a generally cylindrical outer surface for fitment to a receptacle. In this case, bayonet pins emanating from the inner or outer sleeves protrude through the housing. In a preferred embodiment, the inner and outer sleeves are both generally cylindrical bodies and are coaxial.
According to the present invention, there is also provided a container filled with a flowable material having an orifice fitted with a valve device as described above.
Also, according to the present invention, there is provided a method of connecting a container of flowable material to a receptacle including the steps of providing an outlet of the container and the receptacle with corresponding male and female bayonet fittings respectively, providing a butterfly valve in the outlet and rotating the butterfly valve so as to open or close the orifice according to relative rotation of the orifice and at least one bayonet pin of the male bayonet fitting.